DIGITAL MULTIPLIERS
Kind Code:
B1
Abstract of EP0055124
A decimal multiplier operates serially by digit. Each multiplier digit is selected in turn, and a PROM is used to generate the product of the selected multiplier digit with each mutliplicand digit in turn, the products being added into a partial product. Each product is generated in two successive cycles, as a units digit in a units cycle followed by a tens digit in a tens cycle. Thus a conventional singledigit decimal adder is used. Further, there are two carry flip-flops, a units carry flip-flop and a tens carry flip-flop, each being operative only during its respective cycles and holding any carry over through the intervening cycle. Means are provided for skipping a multiplicand cycle if a multiplier digit is 0.
A decimal multiplier operates serially by digit. Each multiplier digit is selected in turn, and a PROM is used to generate the product of the selected multiplier digit with each mutliplicand digit in turn, the products being added into a partial product. Each product is generated in two successive cycles, as a units digit in a units cycle followed by a tens digit in a tens cycle. Thus a conventional singledigit decimal adder is used. Further, there are two carry flip-flops, a units carry flip-flop and a tens carry flip-flop, each being operative only during its respective cycles and holding any carry over through the intervening cycle. Means are provided for skipping a multiplicand cycle if a multiplier digit is 0.
Inventors:
Negi, Virendra S.
Tague, Steven A.
Tague, Steven A.
Application Number:
EP19810306018
Publication Date:
01/31/1990
Filing Date:
12/22/1981
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Export Citation:
Assignee:
BULL HN INFORMATION SYSTEMS INC.
International Classes:
G06F7/48; G06F7/52
European Classes:
G06F7/491B; G06F7/52B